#include <iostream>

struct travel_time
{
	int hours;
	int mins;
};

const int Mins_per_hour = 60;

travel_time sum(travel_time t1, travel_time t2);
void show_time(travel_time t);

int main(...){
	using namespace std;

	travel_time day1 = {5, 45};
	travel_time day2 = {4, 55};

	travel_time trip = sum(day1, day2);
	cout << "Two-day total: ";
	show_time(trip);

	travel_time day3 = {4, 32};
	cout << "Three-day total: ";
	show_time(sum(trip, day3));

	return 0;
}


travel_time sum(travel_time t1, travel_time t2){
	travel_time total;

	total.mins = (t1.mins + t2.mins) % Mins_per_hour;
	total.hours = t1.hours + t2.hours + (t1.mins + t2.mins) / Mins_per_hour;

	return total;
}

void show_time(travel_time t){
	using namespace std;
	cout << t.hours << " hours, " << t.mins << " minutes\n";
}